Dynamic host configuration protocol for IPv6

A top feeding device for advancing the upper layer of material in synchronism with the lower layer of material being sewn. The top feeding device includes an upper feed dog moving periodically in conjunction with a lower feed dog to grip and advance the materials being sewn along a path related to the stroke of the stitching needle or needles of the sewing machine. Drive for the top feeder is derived from an eccentric cam mounted on the sewing machine main drive shaft, motion being positively transferred to a pivotal upper feed dog arm by means of a lever arm depending from that arm and being a cam-following surface held under adjustable pressure in contact with the eccentric cam. The pivot for the upper feed dog arm is disposed upon an extension of the main lower feed bar which thereby provides horizontal motion to both the upper and lower feed dog arms.